高强钢板拉伸断口分层缺陷成因探讨  

Discussion on Causes of Lamination Defect at Tensile Fracture of High Strength Steel Plate

作　　者：杨云清[1] 雷辉[1] 高擎[1] 李玉路[1] 杜江[1] 袁源[1] 

机构地区：[1]华菱集团湘潭钢铁有限公司

出　　处：《宽厚板》2013年第1期5-10,共6页Wide and Heavy Plate

摘　　要：对高强钢板常见拉伸断口分层缺陷的成因进行探讨,利用金相及扫描电镜观察拉伸试样断口组织、裂纹和钢中夹杂物,采用X射线衍射法测量分层试样的位错密度。研究发现钢板基体较高的位错密度是导致试样断裂过程中产生分层的主要原因,而夹杂物、晶界等缺陷是裂纹的起裂点,研究还发现分层与偏析、微观组织类型等无明显相关性。通过降低高强钢板的屈强比,可以显著改善分层缺陷。Causes of the common lamination defect at tensile fracture of high strength steel pate have been invest igated. The microstructure, cracks and inclusions at tensile specimen fracture have been observed by means of metallo- graphic microscope and SEM methods, the dislocation density of specimen with lamination defect measured by X - ray diffraction method as well. The results show that the high dislocation density of steel matrix is the major cause of the lamination in the process of specimen fracturing, defects such as inclusions and grain boundary are tile origin of cracks, and the lamination has no apparent correlation ~ith the type of segregation and microstructure. Tile lamination defect can be notably improved by reducing the yield - tensile ratio of hizh strenzth steel.

关 键 词：高强钢板 拉伸断口 分层 位错密度 

分 类 号：TG142.1[一般工业技术—材料科学与工程]